A good book I read on a lot of these issues prior to buying is " The Canadian Snowbird in America" by Terry F Ritchie and Brian D. Wruk who are accountants specializing in Canada/U.S. tax situations. It is available on Amazon.com.
According to one section in the book with property held jointly the title passes to the survivor but the IRS will automatically assume that in the event of the death of a spouse the spouse that passed away contributed 100% of the cost of the house unless the surviving spouse can prove otherwise and as a result there will be a tax on the total value of the property. It is important therefore that each spouse has it documented the amount that they contributed to the purchase.
